1. Field of the Invention
The present invention relates to an inkjet recording device, and a method of releasing a cover lock of the inkjet recording device.
2. Description of the Related Art
When a recording sheet gets jammed or a carriage operation error occurs in an inkjet recording device, an operator opens a cover and inserts a hand to remove the recording sheet, or moves a carriage to its home position. If the carriage is moved then, it can hit a hand of the operator or the operator can get his/her finger caught therein, which is significantly dangerous. If the carriage keeps printing operation when the cover is opened during printing, the operator may touch the carriage with his/her hand unintentionally, which is significantly dangerous.
Then, it is already known that the movement of a carriage is stopped in response to the detection of opening of a cover at the moment when the cover is opened, in order to avoid the danger.
Moreover, it is also already known that a cover and a housing are locked so that an operator cannot open the cover until printing is finished or an error is detected.
However, the conventional inkjet recording device does not necessarily guarantee the safety because there occurs a time difference between the detection of opening of a cover and the stop of a carriage, depending on detection timing, etc. There is a possibility of failure or malfunction, and the carriage is not necessarily stopped. Therefore, the safety is not sufficient. Even if the cover and the housing are locked, it is possible that when the lock is released and the cover is opened, the carriage is moved due to malfunction of the carriage. In the case where the carriage is stopped in the center of the housing when an error is detected, the carriage is possibly moved when the cover is opened and a hand is inserted in the housing, which can be a problem in terms of safety.
Japanese Patent Application Laid-open No. 2006-142608 discloses a printer and a printing control method. The printer includes an openable cover that covers a moving area of a printing head, a cover state detecting unit that detects the opening and closing of the cover, a printing state detecting unit that detects a printing state, and a lock unit that locks the cover to a housing. For the safe operation of an operator, the cover is locked to the housing during printing operation so that the cover is prevented from being opened, and the lock is released when printing is finished or an error is detected so that the cover can be opened.
According to the conventional technique as described above, the cover is locked to the housing so that the cover cannot be opened during printing operation. However, in the conventional technique, the carriage is possibly moved due to malfunction of the carriage when the lock is released and the cover is opened. Moreover, in the case where the carriage is stopped in the center of the housing when an error is detected, the carriage is possibly moved when the cover is opened and a hand is inserted in the housing. Thus, the problems regarding the safety have not been solved sufficiently.
Therefore, there is a need to provide an inkjet recording device that is excellent in safety and allows an operator to use it safely without a risk of injury due to the movement of the carriage.